Third International Conference on Applications of Mathematics to Nonlinear Sciences. Electron. J. Diff. Eqns., conf. 27 (2024), pp. 63-73. Title: On drug therapy for an HIV infection age model with cellular and immune delays Author: Nicoleta E. Tarfulea (Purdue Univ. Northwest, Indiana, USA) Abstract: We study the effectiveness of drug therapy for an HIV infection age mathematical model that considers both virus-to-cell and cell-to-cell infections, as well as the immune response. As expected, in the presence of perfect inhibitors, the populations of infected cells, virus, and effector cells decay exponentially to zero. When protease inhibitors are used, the production of infectious virions is diminished, as demonstrated in our drug therapy model. Published August 20, 2024. Math Subject Classifications: 34K12, 92D30, 92C50. Key Words: HIV infection; viral age model; drug therapy; inhibitors.